Placer-mining dredge



No. 62I,377.

\ Patented Mar. 2|, I899. G. W. SHEPPARD. PLACER MINING DREDGE,

Application filed Mar. 30, 1898.

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PLACER MINING. DREDGE.

Application filed 1mm 30, 1898.) (I0 llodeh) 2 Sheets-Sheet 2.

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PATENT FFIQEG PLACER-MINING DREDGE.

SPECIFICATION forming part of Letters Patent 1N0. 621,377, dated March 21, 1899.

Application filed March 30, 1898.

T0 aZZ whom it may concern:

Be it known that I, GEORGE W. SHEPPARD, a citizen of the United States, residing at Tallapoosa, in the county of Haralson and State of Georgia, have invented a new and useful Placer-Mining Dredge, of which the following is a specification.

My invention relates to improvements in aplacer-mining dredge employing a swinging crane or boom which carries a dipper-excavator; and the object that I have in View is to obviate certain objections heretofore and now incident to mining placer-gold and also to provide an apparatus by which economy in the structure of the plant and in the practical operation thereof is effected.

In a dipper-dredge it is impracticable to discharge any part of the contents of the dipper on the deck or at any point above the deck, for the reason that the place of drop of the dipper at all points in front of the spud and spud-frame is outside of and beyond the exterior lines of the deck; nor can such discharge be made at any point on or above the deck back of the spuds or spud-frame, for the reason that the position of the spuds and spud-frame will not permit the boom or the crane, as the case may be, to swing far enough around to make such discharge.

The invention consists in the novel combination of elements and in the construction and arrangement of parts, which will be hereinafter fully described and claimed.

To enable others to understand the invention, I have illustrated a preferred embodiment thereof in the accompanying drawings, forming a part of this specification, and in which Figure 1 is a plan view of a dipper-dredge for gold placer-mining constructed in accordance with my invention. Fig. 2 is a front elevation of the parts represented by Fig. 1. Fig. 3 is a view in side elevation, illustrating the hopper and sluiceway supported on one side of the dredge-boat wholly above a line extended from the plane of the deck; and Fig. 4 is a View similar to Fig. 3, but illustrating the hopper and sluicing apparatus in a plane partly above and partly belowa line extended from the deck-surface.

Like numerals of reference denote like and Serial No. 675,740. (No model.)

corresponding parts in each of the several figures of the drawings.

1 designates a dredge-boat of any usual or preferred construction, and 2 is the crane or boom erected at the bow of such dredge-boat in the plane of the central line thereof. This boom or crane carries a dipper or bucket 5., and it is supported on the dredge-boat by vertical pivots 3 4 to enable said boom or crane to swing laterally and discharge its load to one sideof the dredge-boat exterior to the sides or gunwales thereof. With the boom and dipper or bucket is combined the tackle 6 for operating the bucket and the boom, and these parts are driven by an engine(not shown) carried on the dredge-boat.

According to my invention a receivinghopper 8 and a sluicing apparatus 9 are Sup: ported on the dredge-boat exterior to the side lines and gunwales thereof and supported by suitable arms or brackets. The hopper 8 occupies a horizontal position at the bow on either side of the boat exterior to the side line thereof and in a position to receive the discharge from the dipper of the crane or boom when the latter is swung'sidewise. The sluicing apparatus 9 is inclined downwardly from the hopper to give the necessary flow to the load deposited in the hopper, and I prefer to give to the sluicing apparatus an inclination inwardly toward the side of the dredgeboat, as represented by Fig. 1, whereby the sluicing apparatus inclines downwardly from the hopper and inwardly toward the dredgeboat. Said sluicing apparatus discharges to a tailings-chute 10, which extends alongside of the boat exterior thereto and parallel to the side thereof, and said tailings-chute is of less width than the sluicing apparatus, the delivery end of the sluice 9 having an inwardly-inclined side, which joins with the tailings-chute 10. The hopper and the sluice are rigidly attached to and carried directly on the dredge-boat by means of the brackets or arms 11, a part of which are employed to properly support the hopper and the sluice.

The brackets or arms for the hopper occupy IOO are gradually shortened from a point adjacent to the hopper to the point where the sluice comes in contact with the side of the dredgeboat.

lVhile I may employ a single hopper and sluice on one side of the dredge-boat, my invention contemplates the employment of another hopper and sluice on the opposite side of the dredge-boat, and by reference to Fig. 1 this second hopper is indicated at 12, the sluice apparatus at 13, and the tailings-chute at 14:. The arms or brackets 11, which support the hopper 12 and sluiceway 13, are similar in construction and arrangement to the corresponding parts which support the hopper and sluices S 9, respectively. The boom or crane which carries the dipper is mounted centrally at the bow of the dredge-boat, so that it may be swung laterally in either direction to dump its load into one or the other of the hoppers 8 and 12, and in the practical service of the apparatus the dipper is swung first in one direction and then in the other direction to discharge the load alternately into the hoppers placed on opposite sides of the dredge-boat.

As represented by Fig. 3 of the drawings, the hopper and sluieing apparatus on one side of and extereor to the lines of the dredgeboat and its gunnwales are arranged to-lie wholly above the line extended from the plane of the boat-d eck; but this is not strictlynecessary, because the sluiceway may be inclined to have its discharge end extend below the plane of the deck, while the hopper occupies a position above the plane of the deck at the bow end of the dredge-boat. In fact, the hopper and sluieing apparatus may, if desired, be arranged wholly below the plane of the deck and in a position exterior to the line of the boat and its gunnwales.

The common method of employing a separate boat, variously called a sluice-boat, barge, or pontoon, on which to carry and operate the sluice and connected hoppers, entails a heavy additional expense both in the structure of the sluice-boat in operating it and moving it from point to point as the mining operation proceeds. Such prior structures in practical mining operations are limited to a channel and waterway of suiticient width and depth to float both the dredge and its independent sluide-boat side by side in such channel; to a discharge of the entire diggings into a hopper and connecting-sluices, it being impracticable to discharge any part of the load beyond the'limits of the sluiceboat; to a discharge of the entire diggings at one side of the dredge into the sluice-boat which lies alongside of such dredge, and to a discharge of a considerable portion of the tailings after the initial separation thereof onto virgin ground, necessitating a second handling of the tailings. Furthermore, as much of the material moved by the dredging operation, oftentimes the larger part thereof, is barren and contains no values, and as the capacity of a good dredge is much beyond that of a single hopper and connecting-sluices, any structure by which the entire product is necessarily discharged through the hopper and sluices results in a loss of time.

I am aware that prior to my invention it has been proposed to provide a dredge scow or barge with a hopper and a chute located on one side of the barge and to employ a dredging apparatus in the form of a suctionpump or a bucket-excavator arranged to deliver to said hopper. My improved dredging apparatus embraces hoppers and sluices located on opposite sides ofthe boat outside of the gunnwales thereof in connection with a swinging crane or beam carrying a bucketexcavator and located midway between said hoppers and means for swinging the crane and its bucket in opposite directions alternately for the purpose of discharging successive charges of gangue from the bucket into first one hopper and then into the other 110pper, whereby the sluices are able to handle the gangue to the best advantage and the capacity of the dredger as a means for saving gold is increased. My improvements also contemplate the employment of an excavator in which the bucket is arranged to travel on the crane to assume a position beyond the position required for discharging the contents of the bucket into either of the hoppers, whereby the virgin or non-gold-bearing alluvial deposits may at the beginning of the operation be discharged beyond the hoppers,

and this bucket-excavator is controlled by a tackle for adjusting it to the required positions on the crane.

An apparatus constructed in accordance with my invention possesses the following practical advantages: The initial cost of building the apparatus is greatly reduced, owing to the omission of the separate sluice-boat,barge, or pontoon; second, the operator is enabled to discharge at pleasure any part of the excavated material on either side of the dredgeboat into one or the other of the hoppers and sluices or beyond them, thus greatly increasing the sluieing and other capacity of the plant; third, it is not necessary to make or maintain a channel or waterway for an independent sluice-boat, which is often a very important matter, particularly in narrow or shallow streams, where it is frequently a greater burden and expense to float the sluice-boat than the dredge; fourth, it is entirely practicable with such apparatus to operate in streams and other waterways which are too narrow to admit both the dredge and sluice boat; fifth, the dredge-boat is ofttimes able to dig its own way and make its own channel through alluvial deposits j oininga stream and not otherwise accessible to a dredge and sluice-boat side by side; sixth, the employment of hoppers and sluices on either side of the boat provides for the discharge of the paydirt and pay-gravel alternately to said hoppers and sluices, thus giving more time and IIO better opportunity to sluice the same; sev enth, it provides for the discharge of all topping or barren material, generally the larger part of the material moved, directly into the stream beyond the hoppers, thus relieving the sluices of'much otherwise useless work, and, finally, by attaching the sluices and hoppers directly to the dredge-boat, so as to constitute an integral and indivisible part of the structure thereof, all tailings from the sluices can be discharged directly onto ground that has been worked out, and thereby save the second working of any part of the tailings.

In rigging the operating devices for the dipper or bucket the boom is made of such length that its extremity and the bucket when swung around to one side or the other of the dredgeboat will extend beyond the hopper to enable the refuse to be discharged beyond the hopper without passing the same through the sluice-boxes. This is advantageous when the initial work of removing the top layer of soil from the claim is being effected. The guidesheaves for the bucket-rope are placed in positions on the extended end of the boom for the outer pulley to lie beyond the vertical plane of the hoppers when the crane is swung to one side, thus enabling the bucket to 00- cupy the position shown by dotted lines in Fig. 2; but after the top soil has been removed and soil containing the valuable ore is encountered the bucket is caused, by proper adjustment of the rigging, to assume the position shown by full lines in Fig. 2, so that it will discharge the dirt to the hoppers for subj ecting the same to action in the sluice-boxes.

By making the tailings-sluices, which are located at opposite sides of the barge, narrower than the primary sluices, as indicated clearly in Fig. l of the drawings, and at the junction of the respective parts a temporary stoppage of the material is caused at the receivin g ends of said tailings-sluices, by reason of which the dirt back of these tailings-sluices and in the primary sluices or sluiceways is retarded to such an extent as to insure its thorough and complete washing, thereby obtaining the maximum separation of the precious metals in the mass.

It will be understood that my invention is not restricted to a detailed construction of the dredge-boat, dipper mechanism, or the operating means shown and described for supporting the hoppers and sluices, as various changes therein may be made Without departing from the invention.

Having thus described the invention, what I claim is- 1. A mining-dredge comprising a barge or scow, hoppers supported at one end of the barge exterior to the side lines and gunwales thereof and located at opposite sides of the barge or scow at points equidistant from the longitudinal axis of the latter, sluices communicating with the hoppers on opposite sides of and exterior to the barge substantially above the plane of the deck thereof and inclined downward from the hoppers and inwardly into close relation with the barge, tailings-sluices located at opposite sides of said barge and communicating with and at the same inclination as said first-mentioned sluices and said tailings-sluices being narrower than the first mentioned sluices, a swinging crane located near the said hoppers and intermediate the same, an excavatorbucket carried by said crane, and means for swinging the crane in opposite directions to discharge the contents of the buckets into the oppositely-placed hoppers alternately, and

. for also raising and lowering said excavatorbucket, substantially as described.

2. A mining-dredge comprising a barge or scow, hoppers supported at one end of the barge or scow exterior to the side lines or gunwales and on opposite sides thereof, sluiceways communicating with said hopper and inclined downwardly therefrom and toward the opposite sides of, the barge, a pivotallysupported crane disposed intermediate the hoppers and movable about a vertical axis, an excavator-bucket mounted on the crane, mechanism connected with the bucket for raising and lowering the same, and tailingssluices located at opposite sides of the barge or scoW and communicating with, and at the same inclination as, said sluiceways, and said tailings sluices being narrower than the sluiceways, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.

GEORGE W. SHEPPARD. WVitnesses:

Onsoiv HAGER,

RALPH B. HAGER. 

